Experimental and Clinical Studies of Presbyacusis

描述（由申请人提供）：本研究的重点是年龄相关性听力损失（老年性耳聋）。目前，有2800万美国人听力受损，其中约75%的人年龄超过55岁。到2020年，老年性耳聋的发病率将大幅上升。为了应对这一最普遍的残疾状况的挑战，新的信息、诊断方法、康复程序以及具有成本效益的新技术将是非常重要的。预防老年性耳聋和减少其流行是更大的挑战。我们研究项目的总体目标是改进诊断、康复和预防措施。为此，提出了四个研究项目。项目一解决了与老年人在现实听力环境中对言语的理解和助听器的好处有关的基本问题。项目2是一项神经成像研究，旨在研究神经元素的结构和功能，这些神经元素被认为是导致老年人语言识别能力随着年龄增长而下降的原因。项目3通过基因型-表型关联研究，在精心挑选的候选基因中确定与年龄相关的听力损失相关的特定等位基因，并启动旨在描述与年龄相关的听力损失相关的组织病理学变化的研究，以及已知的特定突变。项目4确定了人造血干细胞在维持内耳非感觉细胞中的潜在作用，并描述了衰老和耳蜗损伤对这一过程的影响。此外，两个核心提供行政、技术和科学支持，包括招募人类受试者；人体组织的收集和储存；以及数据的收集、存储和分析。提出的耳聋长期研究方案将影响耳聋患者的医疗保健，影响一般听障人士的护理，并将对听力科学的理论和应用问题产生重大影响。

DESCRIPTION (provided by applicant): The focus of this research is age-related hearing loss (presbyacusis). Currently, 28 million Americans have impaired hearing and approximately 75% of these persons are over the age of 55. The prevalence of presbyacusis will increase substantially by the year 2020. To meet the challenges of this most prevalent handicapping condition, new information, diagnostic methods, rehabilitation procedures, and cost-effective access to new technologies will be of great importance. Prevention of presbyacusis and a reduction in its prevalence are even greater challenges. The overall objective of our research program is to improve diagnostic, rehabilitative, and preventive measures. Toward this objective, four research projects are proposed. Project 1 addresses basic questions related to the understanding of speech and benefit of hearing aids in realistic listening environments by older adults. Project 2 is a neuroimaging study that examines the structure and function of neural elements that are hypothesized to contribute to age-related declines in speech recognition in older adults. Project 3 identifies specific alleles associated with age- related hearing loss in carefully selected candidate genes through genotype-phenotype association studies and initiates studies aimed at characterizing the histopathological changes associated with age-related hearing loss in general, and when known, with specific mutations. Project 4 determines the potential role of human hematopoietic stem cells in the maintenance of non-sensory cells in the inner ear and characterizes the effects of aging and cochlear injury on this process. In addition, two cores provide administrative, technical, and scientific support including recruitment of human subjects; collection and storage of human tissue; and collection, storage, and analysis of data. The proposed program of research on presbyacusis in the long term will influence health care of the presbyacusic patient, will affect care of hearing-impaired persons in general, and will have significant impact on theoretical and applied issues in the science of audition.